Vegetable glues

V.G.Bloede 1918 Amylase Process of manufacturing vegetable glue... 

Adhesives. Adhesives can be considered as coatings between two surfaces. The classic adhesives were water-susceptible animal and vegetable glues obtained from hides, blood, and starch. Adhesion may be defined as the process that occurs when a solid and movable material (usually in a liquid or solid form) are brought together to form an interface, and the surface energies of the two substances are transformed into the energy of the interface. 

The common vegetable glues are based on either starch or cellulose. Unmodified starch dispersed in water is used to form paper pastes but a large proportion is now used in modified forms such as dextrin. Cellulose-based glues are produced by reacting hydroxyl groups present in the polymer chain with different reagents to form a variety of adhesives. 

Vegetable glues Inorganic glues (adhesives, cements)... 

These adhesives are soluble or dispersible in water and are produced or extracted from natural sources. Other adhesives, such as rubber cements, lutrocellulose, and ethyl cellulose lacquer cements, are also produced from plant sources, but are not water-soluble or water-dispersible and are therefore not classified as vegetable glues. 

Adhesive bonding has been in use for many years. Most of the early bonds used animal and vegetable glues, and the structural use of these glues has been confined mostly to timber. 

Vegetable glues Starch Dextrins Soybean glue Rosin... 

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